This invention relates to a process for attaching, in front and rear waist regions of a disposable garment such as a diaper comprising an outer sheet and a liquid-absorbent inner panel attached to the outer sheet, indicator elements which are visually recognizable from the exterior of the garment.
Japanese Patent Application Publication No. 2001-54536A discloses a pull-on disposable article including a patterned sheet and a process for making the same. This diaper comprises a liquid-impervious backsheet lying on the side facing away from a wearer's body (outer layer web), a liquid-pervious topsheet (inner layer web) lying on the side facing the wearer's body, and a liquid-absorbent core interposed between these sheets. This article has a front waist region, a rear waist region, a crotch region extending between these waist regions, a waist-opening and a pair of leg-openings. The patterned sheet adapted to be visually recognizable from the exterior of the article is attached to an inner surface of the outer sheet.
The process for making this diaper comprises a step of attaching the patterned sheet in which the patterned sheet having an area smaller than the outer sheet is attached to the inner surface of the outer sheet at a predetermined location, a step of securing the core in which the core is secured to the inner surface of the outer sheet and a step of joining the sheets in which the inner sheet is placed upon and joined with the upper surface of the core. In the step of attaching the patterned sheet, a plurality of the patterned sheets are successively fed onto the inner surface of the outer sheet so as to be spaced one from another by a predetermined dimension in a longitudinal direction of the outer sheet and then these patterned sheets are attached to the outer sheet by means of a hot melt adhesive.
According to the process for making the diaper as disclosed in the above-cited Publication, a plurality of the patterned sheets must be individually fed onto and attached to the inner surface of the outer sheet with each pair of the patterned sheets being spaced apart from each other by a predetermined dimension in a transverse dimension. Feeding and attaching of these patterned sheets inevitably doubles time and labor and require the additional device as well as steps associated with such feeding as well as such attaching. Consequently, it is impossible to manufacture the diapers at a low cost.
It is an object of this invention to provide a process for attaching indicator elements all at once on surfaces front and rear regions of the diaper.
According to the present invention, there is provided a process for attaching, in front and rear regions of a disposable garment which comprises an outer sheet and a liquid-absorbent inner panel attached to the outer sheet, indicator elements which are visually recognizable from an exterior of the article.
The improvement according to the present invention is characterized by that the process comprising the steps of: feeding a plurality of liquid-absorbent cores each having front and rear end zones and an intermediate zone and running in a machine direction onto an inner surface of one of a continuous first outer layer web and a continuous inner layer web running in a machine direction and destined to be the outer sheet while feeding a plurality of indication sheets each extending in the machine direction and having the indicator elements in front and rear halves thereof, respectively, at regular intervals in the machine direction onto an outer surface of the first outer layer web; placing the intermediate zone of the core between each pair of the indication sheets adjacent to each other in the machine direction, so that a rear half of a front one of the indication sheets adjacent to each other in the machine direction is placed upon the front end zone of the core, and a front half of a rear one of the indication sheets adjacent to each other in the machine direction is placed upon the rear end zone of the core; joining the indication sheet to the first outer layer web, joining the core to at least one of the inner layer web and the outer layer web and joining inner surfaces of the inner layer web and the outer layer web overlaid; forming a panel by cutting the indication sheets together with the inner and outer layer webs in a cross direction between a pair of the cores adjacent to each other in the machine direction so that the indication sheet is divided into the front and rear halves to obtain a plurality of the inner panels arranged in the machine direction; and placing the inner panels at regular intervals on an inner surface of a continuous outer web running in the machine direction after the inner panels are turned round in the transverse direction approximately by 90° and joining the outer surface of the first outer layer web to an inner surface of the outer web.
The present invention includes the following embodiments.    (1) The process further includes the steps of cutting the outer web in a transversely middle zone to form a plurality of openings arranged at regular intervals in the machine direction then, placing between each pair of the openings adjacent to each other of the outer web after turning round the inner panels approximately by 90° to a cross direction and cutting the outer web in the cross direction between each pair of the inner panels adjacent to each other to form a plurality of the garment arranged in the machine direction.    (2) The process further includes the stop of turning round the inner panels approximately by 90° to a cross direction while placing the inner panels on the inner surface of the outer web at regular intervals in the machine direction and then, cutting a transversely middle zone of the outer web extending between each pair of the inner panels adjacent to each other to form a plurality of openings arranged at regular intervals in the machine direction; and cutting the outer web in the cross direction between each pair of the inner panels adjacent to each other to form a plurality of the garment arranged in the machine direction.    (3) The process further includes the steps of placing an inner surface of a continuous second outer layer web running in the machine direction upon the outer surface of the first outer layer web, joining the first outer layer web to the second outer layer web; cutting the indication sheet together with the first and second outer layer webs and the inner layer web in the cross direction between each pair of the cores adjacent to each other in the machine direction; and joining the outer surface of the second outer layer web to the inner surface of the outer web.    (4) The process further includes the step of attaching first stretchable elastic members lying on both sides of the core and extending in the machine direction in a stretched state to one of an inner surface of the first outer layer web and an inner surface of the inner layer web.    (5) The process includes the step of attaching the first stretchable elastic members lying on both sides of the core and extending in the machine direction in a stretched state to one of the outer surface of the first outer layer web and the inner surface of the second outer layer web.    (6) The process further includes the step of attaching second stretchable elastic members lying on both sides of the outer web and extending in the machine direction in a stretched state to the outer web.    (7) The first and second outer layer webs are formed by one of a moisture-permeable hydrophobic fibrous nonwoven fabric and a moisture-permeable liquid-impervious plastic film and the inner layer web is formed by a hydrophilic fibrous nonwoven fabric.    (8) The outer layer web is formed by one of a moisture-permeable hydrophobic fibrous nonwoven fabric, a composite nonwoven fabric consisting of moisture-permeable but hydrophobic fibrous nonwoven fabric layers laminated one with another and a composite sheet consisting of a moisture-permeable but hydrophobic fibrous nonwoven fabric and a moisture-permeable but liquid-impervious plastic film laminated with each other.    (9) The indication sheet is formed by one of a moisture-permeable but hydrophobic fibrous nonwoven fabric and a moisture-permeable but liquid-impervious plastic film.    (10) The indicator elements comprise a pair of illustrations printed on the front and rear halves of the indication sheet and adjacent to each other in the machine direction.